exam 2 ch 13 Flashcards
The branch of evolutionary biology that studies the diversity of reproductive
strategies
life-history analysis
Have a high growth rate but low survivability (“cheap” offspring)
r-selected species
Have a low growth rate but high survivability (“expensive” offspring)
K-selected species
Changes in life history are caused by changes in the?
allocation of energy
Number of gametes produced by an individual
Fecundity
selection will favor the number of offspring that results in the most surviving
offspring
Lack’s Hypothesis
individual offspring survival decreases with increasing offspring number
Trade-off
Energy contained in the offspring themselves
Direct costs
Energy expended to produce and carry them
indirect costs
- (a) There is a trade-off between size and number of offspring.
- (b) Above a minimum size, the probability that any individual offspring will survive is an increasing
function of its size
Selection on Offspring Size
Assumptions
selection on Offspring Size
-Selection on parents favors a compromise
between the quality and quantity of offspring,
-Selection on individual offspring favors
high quality
Fertilization of two or more ova from the same cycle by sperm from separate
acts of sexual intercourse
Superfecundation
Only one copy of a gene in an individual (from mother or father) is expressed,
while the other copy is suppressed
Genomic imprinting
A growth promoting hormone.
Insulin-like growth factor II
A receptor that binds IGF-II to promote
lysosome activity
Cation-independent mannose-6-phosphate receptor (CI-MPR)
When mates are not monogamous, the life-history strategy that is ___________________________ for the other
optimal for one sex may be
suboptimal